2 barrel , 4 barrel, whose got the answer?

Well these are my thoughts, its a van so I am assuming cruising and hauling, but I have seen a Dodge van or three with a 440 in it in my day so performance I get it. The 318 , try both carburetors see which one performs and record gas mileage etc. 318 is the economy utility V8 so either way you may be surprised. Ill add that with a 318putting on an induction system also needs an ehaust sytem to go with it then after that the bottleneck is the heads. Slapping a 4 barrel on a 2 barrel van and doing nothing else may just result in poor mpg IMO